TRANSFORMATION BY AVIAN RETICULOENDOTHELIOSIS VIRUS

禽网状内皮组织增生症病毒(REV-T)是 都是逆转录病毒。Rev-T癌基因、v-rel、转化和 阻止淋巴细胞随后的分化 B细胞发育的不同阶段。REV-T转换为正常 细胞进入致瘤状态，提供了一个极好的模型 致癌机制的研究。V-rel癌基因是不同的 从其他已知的癌基因中分离出来，并编码一个59 kDa的蛋白质，它是 与一组不同的细胞蛋白质相关。 有两个pp59v-Rel胞浆复合体，包含 原癌基因c-Rel的产物(p75c-Rel)及其构成 热休克蛋白70的形式(P70hsc)。主要的胞质 复合体的独特之处在于它含有一个40 kDa的磷酸蛋白 (第40页)。胞浆中20%的pp59v-rel不是 与pp40有关，但与两种高分子量蛋白质有关 (第115页，第124页)。纯化的pp59v-Rel胞浆复合体含有一个 相关的丝氨酸激酶活性。约10%的 Pp59v-rel存在于含有pp40的核复合体中。 在正常禽类淋巴样细胞中，p75c-rel与蛋白质形成络合物。 具有与pp59v相关的相同表观分子质量- REL导入REV-T转化细胞。主要的p75c-rel复合体 包含p115和p124。丰度较低的复合体含有p75c- 与pp40关联的REL。 C-rel原癌基因和v-rel蛋白激活转录 在酵母中负责激活的区域也是 是v-Rel致癌转化所必需的。但是，在 正常和转化的禽类淋巴样细胞p75c-rel是胞浆 蛋白。P75c-rel很可能是一种反式激活因子 被隔离在未受刺激的淋巴样细胞的胞浆中。什么时候 REV-T转化细胞暴露于重金属，p75c-rel 水平增加，核移位发生。目标 这项建议的目的是1)对v-rel进行突变分析，以 转化能力与细胞结合的相关性 蛋白质到v-rel蛋白；2)确定是否有任何这些 与p75c-rel相关的蛋白质参与核 3)对编码基因进行分子克隆和测序 Pp40并确定其组织特异性表达；4)制备 抗相关细胞蛋白的单抗 Pp59v-rel和p75c-rel。

Avian reticuloendotheliosis virus (REV-T) is the most virulent of all retroviruses. The oncogene of REV-T, v-rel, transforms and prevents the subsequent differentiation of lymphoid cells at different stages of B cell development. REV-T converts normal cells to a tumorigenic state providing an excellent model for studies on oncogenic mechanisms. The v-rel oncogene is distinct from other known oncogenes and encodes a 59 kDa protein which is associated with a distinct set of cellular proteins. There are two pp59v-rel cytosolic complexes which contain the product of the c-rel proto-oncogene (p75c-rel) and the constitutive form of heat shock protein 70 (p70hsc). The major cytosolic complex is distinct in that it contains a 40 kDa phosphoprotein (pp40). Twenty percent of pp59v-rel in the cytosol is not associated with pp40 but with two high molecular weight proteins (p115, p124). Purified pp59v-rel cytosolic complexes contain an associated serine kinase activity. Approximately ten percent of the pp59v-rel is present in nuclear complexes which contains pp40. In normal avian lymphoid cells p75c-rel is complexed with proteins of the same apparent molecular mass as those associated with pp59v- rel in REV-T transformed cells. The major p75c-rel complex contains p115 and p124. The less abundant complex contains p75c- rel associated with pp40. The c-rel proto-oncogene and v-rel proteins activate transcription in yeast and the region responsible for activation is also necessary for oncogenic transformation by v-rel. However, in normal and transformed avian lymphoid cells p75c-rel is a cytosolic protein. It is likely p75c-rel is a transactivating factor which is sequestered in the cytosol of unstimulated lymphoid cells. When REV-T transformed cells are exposed to heavy metals, p75c-rel levels increase and nuclear translocation occurs. The objectives of this proposal are to 1) perform mutational analysis on v-rel to correlate transforming ability with the binding of cellular proteins to the v-rel protein; 2) determine whether any of these proteins associated with p75c-rel are involved in nuclear translocation; 3) molecularly clone and sequence the gene encoding pp40 and define its tissue specific expression; 4) prepare monoclonal antibodies against the cellular proteins associated with pp59v-rel and p75c-rel.